Multicasted computers will not image again

I am running netware 6.5 sp5 Zen 7. I have been testing zenimage
process. Yesterday I did a multicast between my 2 test computers one as
master and the other as the client. The test went fine. This morning I
cam in to image the PC's again through unicast and niether will connect
through pxe boot any more. I have fdisked and formated the hard drives
and loaded a base windows install on one. I have taken the test hard
drive and put it in a another pc and it will not connect. I can take
another system and it boots straight to the pxe menu as it should. What
do I need to do on these systems to get them to image again.